Subsoil plow



Sept 14, 1954 2 Sheets-sneet l Filed Jan. 27, 1951 m.. wilma IN11/ EN TOR;

C. R. ADAIR SUBSOIL PLOW Sept. 14, 1954 Filed Jan. v27. 1951 2 Sheets-Sheet 2 INVENTOR.'

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Patented Sept. 14, 1954 UNITED STATES PATENT OFFICE SUBSOIL PLOW Charles R. Adair,` Chicago Heights, Ill. Application January 27, 1951, Serial No. 208,198

l 7 Claims. l.

My invention relates to a sub-soil plough. My sub-soil plough is particularly useful when it is desired to shatter the sub-soil without turning the surface-soil or bring-ing any of the subsoil to the surface. This application is a continuation-in-part of my application U. S. Ser. No. 70,976, iiled January 14, 1949, for Digger Apparatus.

For a considerable period of time an acute need has been felt for a plough which would break up the sub-soil and render it more porous. This need has been felt in connection with various special soil problems. One such problem is that over a large part of the midwestern prairies the surface soil or top soil is only a few inches thick and then shades gradually into the underlying sub-soil. This sub-soil is generally ccmposed of a tough clay and is tight, heavy and hard to manage. Water goes through such subsoil very slowly; and as a result, flat land stays wet and water runs quickly olf the slopes, carrying good top soil with it.

A still wider need for a means for breaking up the sub-soil has been felt because of the socalled plough sole, which is a hardening of the soll produced by the lower part of the plough blade in normal ploughing operations. Also, it is frequently found that uncultivated land such as grazing land is not sufciently water absorptivebecause ofy the tightness of the sub-soil.

Thus, it can be seen thatv there has been a Widely felt need for a plough to render the subsoil more porous. However, the only type of plough which has lbeen provided for accomplishing this resultl consists of a chisel having a shank attached thereto and a long draw bar. This chisel-type plough has been' used by making a series of gashes inA the soil in order to plough up the sub-soil. fSuch a method of subsoil ploughing, however, is unsatisfactory sinceit brings the sub-soil to the surface, and only breaks up a small portion of the the sub-soil. Moreover, it has been found that such ploughing is time consuming and expensive since a rel atively large amount of power is required to pull achisel-type plough.

Therefore, it is anobject of my invention to provide a sub-soil plough which can be used to break up all ofthe sub-soil when desired withoutbringing. the sub-soil tothe. surface or turning the surface soil. It is another object of my invention to design a sub-soil plough which cany be eiectively used without requiring an undue amount of power which would make the plough--` ing operation.y too expensive for the. value ob-` tained. It is a fur-ther object of my invention to design a plough which will raise and lower a section of the sub-soil and thereby shatter the sub-soil and render it more porous. It is a still further object of my invention .to produce an.

implement for sub-soil ploughing which is-composed of thin pieces of` metal, and therefore easily pulled through the ground without sac-- ther objects and advantages will appear as the` specification proceeds..

I have discovered that the above: objects can be substantially accomplished by providing a plough in which the plough body consists of facing plates extended and turned` to provide av rectangular U-shaped frame, and by attaching;

a Wide V-shaped cutter inclined inwardly and downwardly on` the' bottom of the rectangular frame. I` have also made many important discoveries as tothe important details of construction of such a plough which will subsequently be set out.

The sub-soil plough of my inventionis shown in an illustrative embodimentV in theaccompany-l ing drawings; in Which- Figure 1 is a perspective view of my sub-soil ploughtogether with drawing attachments andy adjusting means; Fig. 2, a fragmentary side View in elevation of the ploughshown in Fig. 1; Fig. 3, a fragmentary front view of my plough showing the detachable cutter plates; Fig. 4, a bot.`

tom viewy of my plough showing thei heel `plates and method of connecting the cutter plates to the base plate; Fig..5, a plan viewof theV-shaped cutter seenfrom theV bottom `in Fig. 4; Fig. 6,. a.

front cross-sectional view of the cutter plates taken in elevation online 6-6 of Fig. 5 ;v Fig. 7, a side cross-sectional view of one of myv cutter plates taken. in elevation on line l-l of Fig. 5; Fig. 8, a perspective view ofthe bottom .of my plow showing amodication in the cutter plates mounting and in the heel plates; Fig. 9,y a side view of. the: modified form' of my plough showny in Fig. 8; Fig. 10, a bottom view of the same modifications; Fig. 11, a top .View of these modications; Fig. 12, a fragmentary front crosssectional view taken in `elevation .on line lf2-A2 of Fig. 11 showing, the relationship between the'Y cutter `plates'andthecentral shoe; Fig.. 1.3, a side cross-sectional viewlv taken in elevation von line:

13--13 of Fig. 10 showing thefmeans of attach'- ingv the kcentral shoe to the. base plate;l Fig. 14

i Figs. 4 and 6. Base plate able cutter plates and heel the rear of base plate 9 so as to engage bolts when they are secured forwardly. Lugs 25 pref- 3 a perspective view of the bottom of the modified form of the central shoe; Fig. 15, a side cross-sectional view taken in elevation on line |5-I5 of Fig. 12 showing the clamping cooperation between the central shoe and the cutter plates; and Fig. 16, a side cross-sectional View atively thin pieces of steel in order that they may be easily drawn through the ground.

In the illustration given, side plates I and II have bottom portions I3 and I4 which are turned inwardly?. I prefer to have inwardly turned portions I3 and I4 equipped with forwardly extending triangular portions I5 and I6 to assist in supporting thebase plates. To the bottom edges of side members II) and II, I prefer to secure a base or plate 9, as shown best in 9 is V-shaped and is attached to side members I0 and II so as to extend downwardly and forwardly therefrom.

Beneath base plate 9, I secure heel plate support fianges I1 andl. Flanges I1 and I8 are attached to the lower edges of side plates I9 and Il and alignedso as to form a right angle with the vertical edges of side plates I0 and II. The structure thus far described comprises a II in facing position. Plates I0 and Il are preferably formed from rel- 4 Overlapping portions 26h tend to prevent soil from being caught between shoe 26 in cutters I9 and 20. As seen more clearly in Fig. 4, shoe 26 is attached to base plate 9 by means of lug 22 engaging slot 2| and bolt 24 threadedly guided in lug 23 and engaging lug 25. It will be seen that this method of detachably fastening shoe 26 is the same as that used edges.

` for cutters I9 and 20.

` bolts 29. While I prefer side plates I0 and II substantially complete sub-soil plough, which can beused satisfactorily by sharpening the forward edge of base plate 9 and providing means for drawing the plough while holding side members I0 and II in an upright position. I have found it important, however, to utilize detachplates which can be easily replaced when they become worn. In the embodiment shown, cutter plates I9 and 20 are secured on top of base plate 9. Cutter platesl I9 and 20 have sharpened forwardv edges |90. and 20a which extend `downwardly and forwardly of base plate 9.

nated by I9b and 20h.

Various methods can be used for detachably securing cutters I9 and 29 to base plate 9. In the illustration given, I provide slots 2| in the forward edge of plate 9. The lower portion of these slots is preferably beveled. Lugs 22 are attached to the under surface of plates I9 and 20, and preferably have to engage the beveled portion'of slot 2 I, as shown more clearly in Fig. '1. To the rear of cutters I9 and 20 I provide lugs 23 whichhave bolts 24 threaded into them. I also attach lugs 25 along erably have indentations to receive the ends of bolts 24 and thereby securely lock cutters I9 and 20 to base plate 9. 1

Although cutters I9 and 20 can be used alone,l I prefer to provide a central shoe or cutter point 26 which has a forward cutting edge 26a. extending somewhat in front of cutting edges I9a and 20a. I have found it desirable to equip shoe 26 with lateral portions 2Gb which are adapted tooverlie cutters I9 and 20 at theiry forward I prefer to have the outer ends of cutters I9 and 20 turned upwardly as desiga beveled head portion `jacent cutting edges ofI cutters I9 and 20.- If de- 21a and 28a of `heel sired, the forward edges plates 21 and 28 can be beveled as 4 and elsewhere in the drawings. to bevel the lower forward edges plates I0 and II.

seen in Fig. I alsolprefer IIJa and Ibof In addition to the structure thus far described, I have discovered that it is important to locate llet or gusset plates 3U and 3I in the corners formed by side plates I0 and II and base plate 9. Gusset plates 30 and 3l provide sup.- port for the upwardly turned edges I9band 29h of cutters I9 and 20, but primarily to assist the movement of earth through the plough. In order to prevent the crowding of the cut I prefer to have the rear edges of sdeportions I3 and I4 slightly closer together than the front edges. This tends to make the cut slightly wider than the thickness of side members I0 and Il, and is particularly important when the plough is turned without removing it from the ground.` I prefer to draw my plough through the ground with side members I9 and II in an upright position by means Aof drawing linkages similarto those shown in Fig. l. At an intermediate point on side members I0 and II I provide holes 32 to serve as connection pointsfor Near the top of side plates I0' and II., slots 34 can be provided to receive depth control shaft 35. As viewed in Fig. 1 Vthe right yend of depth control shaft 35 is rotatably secured within slots 34 by means of a U-shaped clamp.3I.l On the outside of member II togglev arm k31 isrigidly secured to the end of depth control'v shaft 35. `If desired, a washer 38 can belocated von rod ,35 between toggle arm 31 andside member II. A larger toggle arm 39 is rigidly secured to the other end of rod 35 on the outside. Thrust. bars 4U are pivotally secured to toggle arms 31 an'd 39, and together with draw'bars 33 are'extended forwardly to be pivotally secured to connecting posts 4I. In the illustration given, connecting. posts 4I are equipped with threaded bolts 42 which provide for the clampingof shims 43 between connecting post 4I and tractor axle housmg.

In order to provide for the raising and'l lowering of the plough, lifting booms 44 are pivotally secured to post 4I between draw'bars' 3-3'and thrust bars 49. Lifting booms 44 have links 45 pivotally attached to theirrother ends.' 'Links 45 extend downwardly toward draw bars' 33 at" a point between side members I0 and. II and post 4I, and. are pivotally connected to draw bars 33.' Brackets 45 are rigidly connected to lifting. booms 44 so as toextenddownwardly therefrom bedraw barsv i .33.-

5, tween post 4| and links 45. The lowerends of brackets 46 are adaptedV to beconnected to the hydraulic cylinders of a tractor designated as 4;'IinFig. 1.

The upper end of large toggle arm 39 is equipped with a threaded lug- 48. A rod 49 having a threaded end portion is received within lug 48. In the illustration given, rod 49 is equipped with aA crank 5I) on the forward end thereof tov assist lnturning rod 49. It willbe apparentv that other turning adaptationsl can: readily be used. A support 5I forrod 49 is attachedto side member I0. In the embodiment shown, support 5| is V- shaped having arms 5Ia and 5Ib. Both arms Sla.v and 5|b are rigidly secured to side member III-l If desired, arm Sla can extend between toggle arm 39 and side member I0 having an opening therethrough for turning rod 35. Adjacent the outer end ofv support arm 5I,` rod 49 is equipped with a sleeve 52 within which rod 49 is free to turn. The adjacent end of support 5I is` rigidlysecured to the exterior of sleeve 52. If desired, collars 53 can be rigidly secured to rod 49,- so as to abut the ends of sleeve 52 and thereby restrain the longitudinal movement of rod 49 within sleeve 52. If desired, a thrust bearing may be used between collar 53 and sleeve 52 to reduce friction.

Operation My sub-soil plough can be conveniently used with the drawing linkages shown in Fig. 1,. These linkages provide a convenient means for allowing the plough to be adjusted for depthl or to be raised and lowered in the ground by means of hydraulic cylinders. Connecting posts 4| are fastened to the frame of a tractor by means of shims 43 and bolts 42. In some models of tractors, hydraulic cylinders v4'I are provided on the sides of the tractor, and the piston rods within the-cylinders can readily be connected to brackets 46. From an inspection of Fig. 1, it will be readilyl apparent that the movement of piston rods 48 to the rear willvcause lifting booms44 to be raised andthereby side members III and |I will be raised` Conversely, when piston rods 48 are moved forwardly, lifting booms 44 are lowered, which will thereby cause the plough to be lowered.

In my plough structure, the relationship between the forward edge of the V-shaped cutter and particularly the forward edge of the central shoe and the bottom surface of the heel plates is extremely important in achieving proper regulation of the depth ofcut. Preferably, the heel plates are positioned at the same depth and inclination as theportions of the forward edge of the cutter immediately in front of the heel plate. In this position, the heel plates ride on the bottomof the cut `or furrow, while the side members are in an up-right position.

To change the depth adjustment of the plough, the -length of thrustbars 40 is varied by rotating turning rod 49 by means of crank 5|) to actuate toggle arms 37 and 39. Varying the length of thrust bars 40 varies the inclination of side members I and when the cutter is above ground; As the plough is drawn forwardly, the cutter sinks intorthe ground and the plough gradually swings to an upright position until the selected depth is'. reached at which theheel plates are on the bottomA of the furrow and therefore hold the plough at that depth.

In operation, my plough is lowered by means of hydraulic cylinders 4'I and is ladjusted for proper depth of cut by means of crank50. The plough is then` pulled` into-theground until it assumes anupright position with. the heel'plates on the bottom of` thefurrow. In` this position, it will maintain' the depth of. cut whenv pulled through the ground. While pulling the ploughv through the ground, the soil is made to pass over theV cutter and betweensideplatesicand I I. The ploughed portion of the soilis thus-raised and allowed to fall a distance of threeto four inches, which causes it to be shattered without turning theL topsoil or bringing the sub-soil to the surface. It will be noted that in this operation, all of the. displacement of the soil is in a vertical direction, which is very important in achieving alight draft. l

I have foundthat my plough is relatively easy to pull and that the soil does not readily pack or clog between sides I0 and I I. The raising and lowering of the soil by means of the upward and inward inclination of the V cutter tends to prevent the packing of the soil so as to clog-the plough. Gusset plates 30 and 3| arealso important in preventing my plough from becoming 'clogged with soil. The rectangular shaped configuration of my plough provides astrong'structure even though plates I0 and I| are made of relatively thin metal. It will be apparent that gusset plates-30 and 3| also serve to giveadded mechanical strength to the cutter support portionof myV plough.

Another problem which has arisen in connection with the` construction of my sub-soil plough is how to construct the cutter plates and central shoe ruggedly enough to prevent `them being damaged by striking rocks, etc., while having their wearing surfaces cheaply replaceable. Along this same line, thereV arises the problem of how to attach the relatively thin replaceable wearing. members so that they can be easily attached and. detached, but will not become loosened while the plough is in use. A still further problem which has arisen is that the wearing of the forward. edges of the cutter plate and central shoe require that a means be provided for adjusting the angular relation of the heel plates in order to properly regulate the depth of cut.

I have found that the above problems can be substantially solved by the modifications inV the structure of my sub-soil plough shown in Figs. 8 to 16 in` the drawings. Therefore from the standpoint of economical replacement of the cutting surfaces when they become worn, means of securing the cutters and the central shoe to the base plate, and regulation of depth of out, the modification shown represents improvements over the structure shown in Figs. 1 to 7. These modifications will now be described.

I have discovered that it is possi-ble to modify the fully overlapping cutter plates i9 and 20 to narrow'cutter plates 54. and 55, as shown more clearly in Figs. 8 and 11. Narrow cutter plates 54 and 55 overlap only the forward portionof base plate 9, extending along the forward edge of base plate 9 from fillet plates 39 and 3| downwardly. I prefer that plates 54 and 55 do not meet in the center but rather have a space therebetween as seen more clearly in Figs. l0 and 12.

In the illustration given, plates 54 and 55 have their under surface equipped withv the lugs 22 which have been previously described in connection with cutter plates I9 and 29. Lugs V22 engage slots '2| and thus prevent any rearward movement of plates 54 and 55. In addition, the upper ends of cutter plates 54 `and 55 are apertured to receive the hook end of J-shapedbolts 56, which 'are loosely inserted within openings in or beneath fillet plates 39. `The rearward ends of J bolts 56 are threaded to receive nuts-51. The

`tightening of nuts 51 cause cutter plates to be pulled rearwardly and restrained at the upper ends against forward motion.

However, bolts 56 and lugsf22 cannot prevent the forward sliding or downward tilting of `cutters 54 and 55 at the center of base plate 9.

The means for preventing this `motion will be described in connection with the modification in central shoe 26. f

In the illustration given, central shoe 26 is `modified to provide a laminated construction.

Specifically, central shoe 26 as shown is composed of a supportI shoe 58 and a shoe point 59. l These members are secured together by means of bolts 60.

l point 59 has a depending lug 62 on each side of the underside thereof which is designed to flatly abut the upper surfaces of cutter plates 54 and 55. Also, support shoe 58 is equipped at its rear with a depending lug 63 having a threaded aperture therethrough. Bolt 64 is received within this aperture and adapted to engage indentation 65 on the rear of base plate 9 as shown. more clearly in Fig. 13. Y

In the illustration given and preferably, support shoe 58 and shoe point 59 are bowed downwardly to provide clearance so that the beveled head of lug 22 can be wedged into solt 2l when bolt 64 is tightened within indentation 65. This causes clamping lugs 62 to be pressed downwardly against cutter plates 54 and 55; thus tightly clamping these plates and preventing them from turning downwardly. In order to prevent any chance of cutter plates 54 and 55 moving forwardly, retaining lugs 66 are provided on the upper inner ends of cutter plates 54 and 55 as seen more clearly in Figs. 8 and l5. Clearance is provided between olamping lugs 62 and retaining lugs 66 in order that the central shoe 26 can be tightly clamped even though slot'2l and indentation 65 have become worn. Preferably, clearance is also provided between the upper surface of retaining lugs 66 and the under surface of shoe point 59 to facilitate clamping. y

As previously pointed out the planar relationship between the heel plates 21 and the forward edges of the cutters and central shoe is important to achieve proper depth regulations. Therefore,

I prefer to provide means for slightly adjusting" the position of heel plates 21 and 28. In the illustration given, wedges 61 are slidably mounted between heel plate support flanges Hand I8 and Y heel plates 21 and 28. As seen more clearly in Figs. 10 and 16 wedges 61 have slots 68 to receive bolts 69. Thus, wedges 61 can be moved inwardly or outwardly between the support flanges and the heel plates to change the elevation of heel plates 21 and 28. Heel plates 21 and 28 are prevented from forward or backward movement during the adjustment of wedges 61 by means of pins 19.

While in the foregoing specification, I have set forth certain structures in considerable detail for the purpose of illustrating single embodiments of the invention, it will be understood that such details may be varied widely by those skilled in the art without departing from the spirit of my invention. y f y I claim:

1. In a sub-soil plough, the combination comprising two side plates secured in facing relation by bracing at the top of said plates, a V-shaped support plate inclined downwardly and inwardly connected to and extending between the bottom portions of said side plates, a narrow cutter plate detachably secured on each side of said support plate and overlapping the forward portion thereof, said plates lbeing secured at their upper ends against forward movement and to the forward edge of said support plate against rearward movement, and a downwardly-bowed shoe member providing a forwardly extending point, said shoeA member overlapping the inner edge portions of said cutter plates and clamping said cutter plates to said support plates by downwardly extending lug means, said shoe member also being attached to the rear vof said support plate and exerting a downward clamping force through said lug means on said cutter plates. f

2. In a sub-soil plough, the combination comprising two side plates secured in facing relation by bracing at the to-p of said plates, a V- shaped support plate inclined downwardly and inwardly attached to and extending between the bottom portions of said side plates, a cutter plate detachably secured on each side of said support plate, and a flat shoe having a forwardly extending point secured in the center of said support, said shoe overlapping the inner edge portions of said cutter plates and clampingly engaging said cutter plates.

3. In a sub-soil plough, the combination cornprising two side plates secured in facing relation by bracing at the top of said plates, said plates having inwardly turned bottom sections, said bottom sections having their rear edges closer together than their front edges, a V-shaped support plate inclined downwardly and inwardly attached near the bottom of said inwardly turned bottom sections, a cutter plate removably secured on each side of said support plate, and a fiat shoe having a forwardly extending point secured in the center of said support plate and clampingly engaging said cutter plates.

4. A sub-soil plough, comprising two thin side plates secured in a facing position by bracing at the top of said plates, said plates having inwardly turned bottom sections with beveled forward edges, said bottom sections having their rear edges slightly closer together than their front edges, a V-shaped support plate inclined downwardly and inwardly attached near the bottom of said inwardly turned plate sections, .fillet plates inclined downwardly and inwardly fastened in the corners formed by said inwardly turned4 plate sections and said support plate, acutter plate removably secured on each side of said support plate, and a flat shoe having a, forwardly extend.

of said plates, said plates having inwardly turned` bottom sections with beveled forward edges, a1 V-shaped support plate inclined downwardly and inwardly attached near the bottom of said bottom sections, gusset plates inclined downwardly andinwardly fastened in the corners formed byv said bottom sections and said support plate, a narrow cutter plate detachably secured on each side of said support plate and overlapping the forward portion thereof, said plates being secured at the upper ends against forward movement and to the forward edge of said support plate against rearward movement, a laminated shoe bowed downwardly with a forwardly extending point clamping said cutter plates to said support plate by means of downwardly extending lugs, said shoe being attached to the rear of said base plate so that when in clamped position it exerts a downward force through said lugs on said cutter plates, and heel plates secured to the bottom edge of said side plates beneath said support plate at the same depth as the portion of the cutter edges immediately in front of said heel plates.

6. A sub-soil plough, comprising two thin plates secured in facing relation by bracing at the top of said plates, said plates having inwardly turned bottom sections with beveled forward edges, a V-shaped support plate inclined downwardly and inwardly attached near the bottom of said bottom sections, gusset plates inclined downwardly and inwardly fastened in the corners formed by said bottom sections and said support plate, a cutter plate detachably secured on each side of said support plate and a flat shoe having a forwardly extending point secured in the center of said support, inwardly turned support flanges secured to the bottom edge of said side plates, heel plates se cured beneath said support flanges, and a slidably mounted wedge plate secured between said support anges and said heel plates, whereby the elevation of said heel plates can be adjusted.

7. In a sub-soil plough, the combination comprising two thin side plates secured in facing re lation by bracing at the top of said plates, a V- shaped support plate inclined downwardly and inwardly attached to and extending between the bottom portions of said plates, gusset plates inclined downwardly and inwardly fastened in the corners formed by said side plates and said support plate, a narrow cutter plate detachably secured on each side of said support plate and overlapping the forward portion thereof, said plates being secured to the forward edge of said support plate against rearward movement and having upwardly turned outer end portions resting against said gusset plates and secured against forward movement by means of attachmentbolts extending rearwardly from said upper end portions between said gusset plates and said side plates, a shoe member positioned centrally on said cutter plate and providing a bearing surface overlying both of said cutter plates, said shoe having an extension interlocking with the forward edge portion of said support plate and having tensioning means carried by its rear portion and acting against the rear edge of said support plate to clamp said shoe to said support plate and to cause the bearing surface of said shoe to press downwardly against said cutter plates.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 124,810 Goodwin Mar. 19, 1872 145,627 Clark Dec. 16, 1873 326,462 Torrey Sept. 15, 1885 547,500 Poole Oct. 8, 1895 1,314,394 Grimes Aug. 26, 1919 1,894,516 Karstadt Jan. 17, 1933 1,909,752- Calkins May 16, 1933 2,154,970 Briggs Apr. 18, 1939 2,190,347 Austin Feb. 13, 1940 

